Printing plate mounting



2 Sheets-Sheet l Aug. 6, 1940. w. F. BRUGMANN PRINTING PLATE MOUNTINGFiled April 25, 1936 Y 61 56 46 HL2 I 7 v u. 0 w Y f L 2+ m@ 7 l. 4 U na n J w y `u u Q/V ATT N EYS.

Aug, 6, 1940. w. F. BRUGMANN PRINTING PLATE MOUNTING Filed April 25,1936 2 Sheets-Sheet 2 w: ,....imwu A N a INVENTOR,

BY y

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Patented Aug. 6, 1940 UNITED STATES PATENT oEFIcE 2,210,749 PRINTINGPLATE MOUNTING William F. Brgninnn, Evanston, III. Application Apiil 25,1936, serial. N10. 76,454 rclaims. (c1. i-38s) This invention-relates ingeneral to printing plate mounting devices, and more particularly to anovel rack adapted to be secured in grooves in a printing press platecylinder or other supporting base member, and to the method andapparatus for inserting and repairing such a rack.

While the instant invention is clearly applicable to printing pressplate cylinders andto plate supporting bases for flat bed presses, itisshown 1Ul and described herein in conjunction with the former, sinceits advantages in such an installation are more readily apparent.

The prior art discloses the cutting of=helical grooves in thecircumferential surface of printing press cylinders within whichregister hooks are adapted to be mounted, and the provision of. a rackor racks therein with which driving means, such as gears or Worms, inthe hooks may cooperate to move the hooks longitudinally of the 2ogrooves into and out of clamping engagement with the usual printingplates. These prior'gart racks, however, and the methods-.employedl inmounting them in the grooves in the cylinders have certain practicaldisadwantageswhich it is the purpose of the instant invention toovercome. Heretofore the racks have been pushed or pulled longitudinallyinto T-slots cut adjacent the bottom of the grooves. Since the racks aresub# jected to great strain by the driving elements of :in the hooksboth in their initial registeringi move ments, and during a run by theaction of the im# pression cylinders on the printing plates, undue wearofy certain portions of the racks andbreakage of some of the teeththereof naturally follow in the course of time. In the prior art devicesit is then necessary toi remove the entire rackfrom the full length ofthe groove, even though buta smallportion thereofl has been damaged. Todo this,l

the plate cylinder must be taken out of the press and shipped to thefactory where the necessary tools and equipment are availableto do thework, and, in the meantime, thefpressis completely out of commission.

A principal object of my invention, therefore,

4,-, is the-provision of a novel rack, methodandvapparatus for insertingthe same in a groove in a printing plate supporting member, such as aplate cylinder, from the top of the groove, and riveting it in thebottom portion thereof. l

5() A further object of the invention is the provision of such a rackwhich permits Vthe repairing of any desired portion thereofWithoutfnecessitating the removal from the press oif'the plate`supporting member in which the rack is mounted.V 55 Another importantobject of ythe invention is;r

the provision of a novel method and apparatus for i repairing thedamaged portion or portions of such a rack by removing such damagedportions only and replacing them with new pieces of rack of the samesize. v

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following descriptiomwhich, whentaken in connectionvvith the accompanying drawings, .d-.iscloses a.preferred embodiment thereof. l0

In'the drawings,`

Fig. 1 is an elevational View, with parts broken away, of a printingvplate cylinder and apparatus for inserting racks, embodying therfeatures of the instant invention, in helical grooves in the locylinder;

Fig. 2 is a front elevational view, With the upper 'portion in verticalsection, of the tool holding device of Fig. 1;

Fig. 3 is a side elevational View, partly in sec- 20 tion, ofthe lowerportion of the device of Fig. 2 in operative position in a groove of thecylinder;

Fig. 4 is aV detail rear elevation of the riveting roller; f v n Fig. 5is a top plan view ofthe repair'drill jig 25 mounted in a groove of thecylinder;

Fig. 6 is a `vertical sectional view taken su stantially on the line 6 6of Fig.5`;v

Fig. '7 is a vertical section taken substantially on the line l--T ofFig. 5; 3o

- Fig. 8' is a top plan View of the trimmingtool mounted in a groove ofthe cylinder;

Figs. 9 and l0 are vertical sectional views taken substantially onthelines 9-9 and Ill-lil, respectively, ofFig. 8; l

- Fig. 11 is a` front elevational View of the repair' riveting tool;

Fig. 12 is a bottom plan View of the tool of Fig.

. 11; and

Fig. 13 is a top plan view of a repair piece for the 40.

rack. I

Referring more particularly'to the drawings, reference numeral 2|indicates a printing press plate supporting cylinder o-f well-k nownconstruee tion having end bearing members 22r (Fig. 1). A 45 pluralityof spaced, parallel, helical grooves 23 are cut in the circumferentialsurface of the cylinder 2| in the usual mannenand are preferablydisposed yat an angle of'approximately Llidegrees to thelongitudinal-axis rof the cylinder.

The grooves 23 are constructed to receive any suitable form of plateholding devices, such Vas the printeris registernook disclosed in mycopending application for U. S. Letters Patent, `Serial No. 77,473 filedApril 25, 1936, and are pro- 545 vided on each side adjacent the topwith longitudinal, under-cut recesses 24 (Figs. 3, 6, 9 and within whichthe locking elements of the plate holding devices (not shown) areadapted to be positioned` At their lower ends, the side walls of thegrooves23 are cut back or outwardly at a slight angle and for a shortdistance at 25 to provide a slightly laterally enlarged recess at thebottom of the grooves within which are mounted racks 26 adapted to beengaged by the driving gears of the printers register hooks.

The racks 26 are provided with teeth 21 on their upper surfaces formedintegrally therewith, and with longitudinal, marginal recesses 28 oneither side of andextending slightly below the root line or bottomportion of the teeth 21 (Figs. 5 and 6). When the racks 26 are securedin place in the bottom of the grooves 23, these marginal recesses 28form gutters along the sides of the teeth 21 for the accumulation anddrainage of foreign matter, and also facilitate the securing of therackswithin the grooves 23 in a manner to be later described. The racks26 are also preferably provided with a substantially centrally located,longitudinal recess or groove 29 in the bottom surface thereof forapurpose which will be explained hereinafter.

For positioning the racks 26 in the grooves 23 and securing them inplace, after the grooves have been cut in the printing plate supportingmember` 2|, the following mechanism is provided. Any suitable device maybe employed upon which to mount the printing plate supporting member,this being shown in Fig. l as an ordinary planer, indicated generally byreference numeral 3|. The bed of the planer 3| is provided with theusual driving rack 32 on the under side, by means of which it isoscillated longitudinally (sideways in Fig. l) in well-known manner, andwith the usual longitudinal T-slots 33 in the upper surfaces thereof. Apair of trunnion supporting members 34 are secured to theA bed of theplaner 3| vby the usual T-bolts 35 mounted'inv the T-slots 33. Thetrunnions 34 are adapted to receive the bearing members 22 of the platecylinder 2| to rotatably support the cylinder on the planer bed with itsaxis disposed longitudinally thereof.

If it is desired, a tensioning means of some sort may be provided toresiliently urge the cylinder 2| to rotate in a clockwise direction, asviewed from the rear of the planer 3|, or the right of Fig. 1, for apurpose to be later described. Such a tensioning means is shown in Fig.1 as comprising a coil or clock spring device 36, mounted on the bed ofthe planer 3|, and having one end of a flexible strap or cable 31secured thereto, the other end of which is adapted to be wound aroundand secured in any suitable manner to one of the bearing members 22 ofAthe cylinder 2|. A handle 38 may be provided on the tensioning device36 for winding up and controlling the operation of the spring therein.

The planer 3| is provided with the usual uprights 4l, between which thebed is adapted to reciprocate, cross-brace 42 mounted between theuprights 4| for vertical adjustment, cross-slide 43 mounted for lateraladjustment on the brace 42 by screw 44, and tool holder 45 pivotallymounted at 46 on the slide 43 for forward swinging movements onlyrelative thereto. A rack inserting tool, indicated generally byreference numeral 48, is adapted'to be secured in any suitable manner,as by a U-clamp member 49, to the forward face of the tool holder 45.1

Referring to Figures 2 to 4, the rackinserting bore 52.

y tool 48 comprises a cylindrical body portion 5|,

which is adapted to be engaged by the clamp 49. The body portion 5| isprovided with an axial bore 52, having a decreased threaded portion 53at its upper end. An internally and externally threaded collar orpressure member 54 is screwed into the reduced threaded portion 53 ofthe bore 52, and is provided with an angular head portion 55. A rod 56is disposed within the longitudinal bore 52 of the body portion 5|, andis threaded adjacent its upper end for engagement with the inner threadsof the collar 54. The rod 56 terminates at its upper end in an angularhead portion 51. A collar 58 is disposed within the bore 52 surroundingthe rod 56, and is pressed upwardly against the lower end of the collar54 by a compression coil spring 59, which also surrounds the rod 56, andis disposed within the The lower end of the coil spring 59 abuts againstthe upper end of a vertical cylindrical extension 6| forming a part of atool carrier, indicated generally by reference numeral 62.

The cylindrical extension 6| is disposed within the lower part of thebore 52, and is provided with a bore 63 through which the lower end ofthe rod 56 extends. The extension 6|, and consequently the tool holder62, is held against rotation relative to the body portion 5| in any oneof a plurality of predetermined positions by a setscrew 64, which ismounted in the cylinder 5|,-

and is adapted to engage within a selected one of a plurality of grooves65 in the outer surface of the extension 6|.

The grooves 65 may be spaced around the circumference of the extension6| for a purpose which will be hereinafter explained. Each of thesegrooves is of such a width that the inner end of the screw 64 willfirmly engage its side walls, and is of such a length as to permitlimited vertical movement of the tool holder E2 relative to the bodyportion 5|.

Referring moreparticularly to Figure 3, it will be seen that `the toolholder 62 comprises a rounded rear end portion 66, disposed immediatelybelow vthe extension 6 I and a flattened forwardly extending yokeportion G1, The rear portion 66 is provided with a vertical bore 63,which is coaxial with the bore 63 in the extension 6|. A cylindricaltool carrying member 69 is mounted for sliding movement within the bore68. The upper end of the tool carrier 69 is adapted to be engaged by thelower end of the rod 56. The tool carrier 69 is' held against rotationrelative to the tool holder 62 by a setscrew 1| extending through therear wall of the latter and engaging within a short vertical slot orgroove 12 in the surface of the tool carrier 69. The slot 12 is ofsufficient length topermit a certain amount of vertical movement of thetool carrier 69 relative to the tool holder 62.

It will be readily apparent that the cylindrical members 6| and 69 maybe given an angular cross section in order to eliminate the necessity ofusing setscrews 64 and 1| to prevent rotation of these members. If thisis done. however, other means must be provided for limiting the verticalmovement of these members.

The lower end of the tool carrier 66 is formed to provide a narrowdepending yoke portion 13 (Figs. 3 and 4). A double bladed rivetingroller 14 is mounted on the lower end of the tool carrier 69, with theyoke portion 13 straddling the center portion thereof, and is removablyheld in place by a horizontally disposed pin extending Cil ' sion 6| ofthe tool ho1der62.

through the lower ends-of the yoke 13'. Each of the blades of theriveting roller 'Mis provided with a plurality of circumferentiallyspaced teeth '|6. The teeth 'I6 are triangular in yradial cross section(Fig. 4) with their outer surfaces being disposed at a lesser angle to avertical plane than are their inner surfaces. The purpose of so shapingthe teeth of the riveting roller M willv be later described. A pressureroller gear 1'! is rotatably mounted on a cross shaft I8 extendingthrough and supported by the lower forward end of the yoke 6l.Horizontal, forwardly extending guide bars 79 are mounted at their rearends on the outer ends of the shaft'18 on either side of the yoke 67 andguide roller 11, and are held against the outer surfaces of the yoke byretaining nuts 8| threaded on the outer ends of the shaft 7S.

The above described mechanism is used to insert and secure the racks -25within the bottom portion of the grooves 23 in the cylinder 2| in thefollowing manner:

The cylinder 2| is rst mounted in the trunnions 34 with its axisextending longitudinally of the bed of the planer, as shown in Figure 1.The rack inserting tool 48 having been secured to the tool holder l5 ofthe planer and positioned directly above the axis of the cylinder 2|,the

setscrew 64 is unscrewed to permit the setting ofA the tool holder 62 atthe same angle to a vertical plane dened by the axes vof the cylindricalbody portion and the plate-holding cylinder 2|, as the grooves 23 aredisposed relative to the same plane. For this reason a plurality ofgrooves 65 are provided in the outer surface of the exten- Since it issubstantially universal practice to cut the grooves 23 in the cylinder.2| at an angle of 45 degrees to the axis of the cylinder, only one suchgroove 65 may be actually necessary.

The bed of the planerv is run forward sui-- ciently to clear the.uprights 4l, and one end of a rack 26 is placed in the end of one ofthe grooves 23, and manually riveted or otherwise secured therein. Intheir initial form before they are mounted in the grooves-23, the sidewalls of the racks 26 are vertically disposed, and the racks are of sucha width as to permit them to readily slide downwardly into' the fgrooves 23. After they have been loosely positioned in the bottom of thegrooves, downward and outward pressure on their upper surfacesadjacenttheir outer edges will force a certain amount of metal into theangular recesses .'25 to rmly secure them in the bottom of the grooves.

One end of a rack 26 having been secured in the rear end of one ofthegrooves 23 by hand, such portion of the groove 23 is brought beneaththe guide roller Tl, and the latter is lowered into this 'I'he rack 26extends loosely in front of the guide roller 'H and is maintained inline with the groove 23 by the forwardly extending guide bars 19. 'Iheinitial cross vertical adjustment of the riveting tool 48 down into theselected groove 23 is had by moving the tool holder 45. Any desireddegree of downward pressure may be maintained on the tool holder 52,rand consequently the guide roller "H, by adjusting the collar 54 tovary the tension-in the coil spring 59.

The arrangement of these parts is such that the guide roller 'Hisresiliently and not/positively held against vertical movements. Sincethe cylindrical body portion `5| is rigidly held by the clamp 4B,vertical movement of the riveting roller,

'I4 is positively prevented by the rod .56 abutting against the toolcarrier 69. This rod provides. a

`rack 26 in the bottom of the grooves 23.y

means of micrometic adjustment for the riveting roller 14.

The bed of the planer 3| is now moved rearwardly (to the right in Figure1), which carries the cylinder 2| past the riveting tool 48. Since theAguide roller 'H is positioned in the selected -groove 23, the cylinder2| will be rotated by the guide roller as it is moved rearwardly. Toassist inv this rotative movement of the cylinder 2|, the tensioningmeans` 36 may be l,employed as above described. As the cylinder 2|is-moved past the riveting tool 48, the guide roller 'l1 insures properpositioning of the rack 26 in theybottom ofv the groove 23 since theteeth 'of the roller are formed to accurately mesh with those of therack.. For this reason, the guide roller 'l1 may also function as aiinal forming tool for the teeth, 2 of the rack. If it is desired, asuitable shoe may be secured to the tool holder 62 in advance .of `theguideroller Tl to relieve rthe guide roller from the side pressuredeveloped in rotating the cylinder 2|.

The riveting roller i4 is positioned vertically so that its teeth 16will dig into the-upper side surfaces of the rack dened by the'recesses28.v The shape of the teeth 'i6 is such that this will result in asideward deflection of some of the metal into the inclined recesses 25at the bottom of the groove 23. The particular shape o-f the rivetingroller 14 willfalsof insure against any damage being done to the teeth2l of the-rack .in this riveting operation.

It is of course necessary in inserting the racks as above described, toremove the printing plate supporting cylinder from the press. After thecylinder has been mounted in the press, however, the racks 26 may berepaired by use of the mechanism shown in Figures 5 to 13 withoutremoving the cylinder therefrom.

Referring more particularly to Figures 5, 6 and 7, a drilling jig 82 isshown which is substantially rectangular in shape, with the lowerportion thereof adapted to iit slidingly into a groove 23 in the-platesupporting member 2|. The jig 82 is provided with an upper marginalflange 83,

which rests upon the top surface of the plate supporting member 2|^whenthejigy is positioned in a groove 23. is-provided with a plurality ofteeth M, which are adapted to engage betweeny the teeth 27 of theAdjacent each end, the lower portion of the jig 82 is provided with arecess 35, whichcommunicates atits upper end with a vertical bore 36. Aclamping bolt lS'lv is mounted in each of the vbores t6, andis providedat its lower end with an elongated head portion 83 disposed within therecess 85. The upperend of each of the clamping bolts. 8'! is threadedfor engagement by a nut- S9, and is provided with an angular, axiallydisposedrecess or bore 9| (Fig. 5). The center portion of the jig 8-2 isprovided with a plurality of longitudinally spaced bores or aperturesB2, the axes of .which coincide with the longitudinall axis of the jig.Two additional bores or apertures 93 are provided adjacent one of theend apertures 92, -which are spaced to either side thereof and havetheircenter lines-disposed on a cross line at the same angle as theteeth S4 and `2l. l f

When it is desired to `repair a particular portion of one of thevracks26, the drilling jig 82 is inserted into the groove 23 over that portionof the rack which is to be repaired. The teeth 84- of the jig insure itsbeing properlypositioned relative to the teeth 2] of the'rack 26. A keyThe bottom surface of the jigSZ "as to fit loosely within the groove 23.

or tool (not shown) is inserted in the angular recesses 9| to turn theclamping bolts 81. A partial rotation of the clamping bolts 81 will turnthe elongated head portions 88 thereof into engagement with the undercutrecesses 24 in the groove 23. The nuts 89 are then tightened to bringthe head portions 88 upwardly into firm locking contact with the topwalls of the recesses 24 and force the teeth 84 downwardly into thespaces between the teeth 21 of the rack.

The apertures or bores 92 and 93 are then used as guides for a drill ofany suitable construction. The drill will cut downwardly through therack 26, with the groove 29 in the bottom portion thereof insuring thatthe rack is completely cut through without damaging the lower surface ofthe groove 23. It is preferred that a bottoming drill be employed, and asuitable stop collar may be set thereon to limit downward movement ofthe drill by contacting the upper surfaces of the jig 82. This operationhaving been performed, the jig 82 is removed from the groove andreversed end for end and replaced in contact with the sameportion of therack that it engaged in its first position. The drilling operation isAthen repeated.

The apertures 92 are so spaced that these two drilling operations willcompletely cut away the center portion of that part of the rack 26 whichis being repaired. The hole that is cut through the rack as determinedby the end aperture 92 farthest removed from the apertures 93 will haveits center line on the same line as the holes determined by the guideapertures 93 in the reverse position of the jig 82. The end portions ofthat part of the rack 26 being cut out will thus be cut away as shown at94 in Figure 8.

A trimming jig, indicated generally by reference numeral 95, is thenemployed to square ofi the jagged end portions 94, of that part of therack 26 remaining in the groove 23. Referring more particularly toFigures 8 to 10, the trimming jig 95 is rectangular in shape and of sucha size The jig 95 is provided with an upper marginal flange 96, which isadapted to rest upon the top surface of the plate supporting member 2|when the jig is positioned in the groove 23. The bottom surface of thejig 95 is provided with a plurality of teeth 91, which are adapted toengage between the teeth 21 of the rack 26 on one side 'or the other ofthat portion of the rack which has been cut away in the drillingoperation.

The jig 95 is provided with a recess 98 in its lower portion whichcommunicates with a vertical bore 99 having a clamping bolt |0| extendedtherethrough. The bolt is provided with an elongated head portion |02 atits lower end, and is threaded adjacent its upper end for engagementwith a locking nut |03. An angular recess or bore |04 extends downwardlyinto the upper end of the clamping bolt |0I. The members |0I, |02 and|03 are substantially identical, both in form and function, to themembers 81, 88 and 89 of the drilling jig 82.

One of the lower corners of the trimming jig 95 isc-cut away at |05,(Figure 10) and a vertical bore extends through the jig adjacent therear end of this cut-away portion. The lower end of the bore |06 isenlarged to provide an angular chamber within which is slidinglypositioned the lower rectangular head portion of a chisel or cuttingmember |01, which terminates at its lower end in a blade |08. The upperend of the chisel |01 is threaded and extends above the top `tion of therepair piece ||2.

surface of the jig 95. A bolt |09 is screwed on the upper end of thechisel |01 to limit the downward movement thereof, and is held in setposition by a locking nut The trimming jig 95 is positioned in thegroove 23 in the same manner as the drilling jig 82. The teeth 91 insureproper longitudinal positioning of the jig, so that the blade |08 of thechisel |01 will be directly above the side surface of the last remainingtooth 21 of the rack 26 adjacent the cutaway portion thereof. Since theblade |08 of the chisel is disposed at the same angle as the teeth 91and 21, a sharp blow imparted to the chisel will cleanly trim off thejagged edges 94 of the rack that are left by the drilling operation.

If it is desired, two chisels or cutters Y|01 may be mounted, one ineither end, in the trimming jig 95, rather than the one hereindisclosed.

Any loose pieces or chips that are left in the bottom of the groove 23after the drilling and trimming operations have been performed, may beblown out of the groove or removed therefrom with a magnet.

A repair piece ||2 (Figure 13), shaped to t exactly into the blank spacein the rack 26 resulting from the above drilling and trimmingoperations, is inserted into this space in the bottom of the groove 23,and riveted in place with a hand riveting tool, such as that disclosedin Figures' 11 and l2 and indicated by reference numeral H3.

The tool ||3 is substantially square in cross section, and is cut awayat its bottom end to provide a transverse recess ||4. Depending from thebottom of the tool on either side of the recess ||4 are longitudinallydisposed teeth H5. The teeth ||5 have a Vertical cross-sectional' shapesimilar to the teeth 16 of the riveting roller 14 of Figures l to 4. Therecess ||4 is of substantially the same width as the tooth 21 of therack, so that the tool ||3 may be disposed in the slot 23 with the teeth||5 straddling the central por- Downward pressure on the tool ||3 willspread some of the metal of the marginal edges of the repair piece intothe angular recesses 25 at the bottom of the groove to rivet the repairpiece in place.

With the above described mechanism, the racks 26 or any desired portionsthereof may be readily repaired without the necessity of removing theplate cylinder 2| from the press. The longitudinal groove 29 in thebottom surface of the rack 26 acts as a clearance for the drill invcutting through the rack. The same result could be obtained by cutting arecess in the bottom surface of the groove 23. The above describedarrangement, however, is obviously much more desirable.

Should it be necessary to put in a much longer repair piece than thatshown in Figure 13, it would perhaps be easier to cut off the ends ofthe piece in the manner above described, and then cut through itlongitudinally with a saw or narrow milling cutter operating in asuitable fixture. Regardless of the method employed, the longitudinalcutting throughv of the rack 26 permits it to be readily pulled -outfrom under the angular recesses 25 in the groove 23. These recesses 25need not be very deeply cut into the sides of the groove, a fewthousandths of an inch being sufficient to rigidly secure the rack inthe bottom of the groove.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it Will beapparentV rack and the associated Wall of said groove to -facilitateremoval of the rack fromthe groove.

2. A printing plate mounting device, comprising a plate supportingmemberA having a groove therein, and a rack so constructed and arrangedas to be secured in said groove by means'of at least some portions ofits marginal edges being upset against the side Walls of the groove,there being a longitudinal space provided of less width than the rackbetween the bottom surface of said rack and the associated Wall of saidgroove to facilitate removal of the rack from the groove.

3. The method of inserting arack in a groove in aprintingplatesupporting member, comprising introducingthe rack into the groove fromthe open top of the groove, and rigidly securing the rack in the bottomof the groove by upsetting portions of the rack against the side Wallsof the groove.

4.l The method of inserting a rack in a longitudinal groove in aprinting plate supporting member having recesses in the side Wallsadjacent the bottom of the groove, comprising introducing the rack intothe groove from the open top thereof, and securing the rack in thebottom of the groove by displacing portions of the rack laterally intosaid recesses.

5. .The method of repairing a rack mounted in a groove in a printingplate supporting member, comprising removing a selected portion only ofsaid rack, and securing a similarly constructed piece of rack in saidgroove as a replacement for said removed portion by upsetting portionsof said piece of rack against the side Walls of the groove.v y

6. The method of repairing a rack mounted in a groove in a printingplate supporting member, comprising removing a selected portion only oisaid rack, trimming the ends of the rack remaining in the grooveadjacent the removed portion, and securing a fitted piece of rackin saidgroove in place of said removed portion by upsetting portions of saidpiece of rack against the side Walls of the groove.

7. The method of repairing a selected portion of a rack mounted in thebottom of a groove in a printing plate supporting member, comprisingcutting through said selected portion along lines adjacent the endsthereof and a line extending longitudinally thereof, trimming the endsof the rack dened by said selected portion, and securing a fitted pieceof rack in said groove in place of said selected portion.

WILLIAM F. BRGMANN.

